We love to joke about the magic of welding. A shadowy shaman metal crafter takes your broken thing or pile of parts, disappears behind a mostly opaque curtail, says a spell, waves a wand, makes hellish noises. Poof! In a dissipating cloud of smoke, a welder reemerges, holding a finished product worthy of a response like, “Hey, thanks, looks great! Can I buy you a Coke?”
Of course, all of that is old timer’s mythmaking, but I still enjoy holding on to a bit of mystery in the trade. Still, what about some truly mind-boggling shit when it comes to working with metal? What kind of crazy things have you witnessed while welding that left you with a blank stare and asking hella questions?
“The most common ailment of all men, the strange and perverse disinclination to believe in a miracle.” – Rod Serling, “The Twilight Zone”
I’ll share a couple of my own, both dealing with grounds. One, it turns out, had an easy answer. The second, I remain unsure.
First one – CSI: Weldshop
I was welding in a booth at the General Dynamics Land Systems prototype shop, with acorn tables on either side of me. I had a Miller Dynasty 700 grounded to one table and a Dynasty 350 hooked to the other, working projects on both sides. Knee deep into one of them, in the middle of a bead, it suddenly occurred to me that I was using the wrong torch. How is this happening? The torch in my hand was grounded to the table behind me, not the one I was working on. And it welded like butter! I was confused.
I looked around to see if any answers jumped out. I talked about it with a couple of other guys in the shop. I don’t recall which of us had the lightbulb moment first, but the reason was clear: The tables must be grounded to each other below the concrete. Both were anchored down at four corners, and at least one anchor bolt from each table had to be touching the same piece of rebar. Case closed.
Second one – Mind-blowing loop
This happened with a Lincoln Powerwave 500. While using GMAW-p to put together a large aluminum box for the airflow lab, part of a test apparatus for a new tank, I used an overhead crane to flip and spin it around to access the joints to be welded. Sometimes I’d have to remove the ground during this process. Now situated, I struck an arc on an outside lip. It welded OK, but not great. I turned to the machine and played with the trim and wire speed. It still welded, just not as nice as I’d like. I flipped up my hood and again turned to the machine. My eyes grew, and my brain blew as I realized the ground was resting on the machine. Nothing was connecting the machine to the table or the part!
Now, I have an idea of what might have happened. Maybe somehow, it grounded internally and through the gun, so it completed the loop with itself when I pulled the trigger. I’m no engineer or electrical mastermind, and I’ve never had anything like that happen to me in 20-plus years of welding, but that’s my best guess!